A Case Report and Literature Review of Fetus in Fetu – A Rare Aberration of Embryogenesis in a 22-month old Infant

Ma. Femie Japitana, Josefa Hilado, Lysa Lynn Libanan


Fetus in fetu (FIF) is an uncommon pathology resulting from an abnormal embryogenesis occurring in a diamnionic, monochorionic twinning during pregnancy. It is so rare that there is only one underdocumented case reported in the Philippines. We are faced with a curious case of a 22-month old male child who presented with a gradually enlarging abdomen, diagnosed as FIF as confirmed by radiologic studies. After undergoing the necessary laboratory and radiologic work-ups, the patient was stabilized and eventually cleared for surgery. He underwent exploratory laparotomy with excision of FIF, from which a fetoid structure was recovered. Thorough gross and further radiologic evaluation of the recovered fetoid structure reveals findings that fulfilled the diagnostic criteria of a FIF.


fetus-in-fetu, teratoma, intra-abdominal mass, fetoid

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